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MatthiasSomm

Black smoke and engine indicator light: alarming symptoms in 2020 Mercedes Viano Diesel

Check engine light on

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Shaking while idling

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Car won't start

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Unsteady engine

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Stalling while idling

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Black smoke from exhaust on acceleration

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Poor fuel economy

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Jerking on acceleration

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Loss of engine power

Hey guys, I'm worried about my 2020 Mercedes Viano with a diesel engine and a good 55422 km on the clock. I've noticed a few worrying symptoms recently. When accelerating, black smoke comes out of the exhaust and the check engine light is on. In addition, the engine's performance has been diminishing, it runs unevenly, jerks when accelerating and sometimes won't start. Fuel consumption has increased enormously and sometimes it simply stalls when idling, but shakes noticeably. I suspect it could be a problem with the ignition coil or misfiring. Have any of you had similar experiences and can tell me about your experiences at the mechanic? Is it bad if I ride it a little longer? I would be grateful for any advice. Best regards!

(Translated from German)

7 comment(s)


Best Answer

TweissRacer

Hi, your symptoms remind me of the problems I had with my 2017 Mercedes Vito. Just like yours, the check engine light came on and the engine no longer ran smoothly. In my experience, it wasn't a problem with the ignition coil or misfiring, but a faulty engine control unit. The whole thing was definitely serious, the engine performance was severely impaired and sometimes the engine even stopped idling. Nevertheless, I can reassure you that after replacing the control unit, the car ran like new again. It is not advisable to drive around with this problem any longer, as it can lead to major engine damage. I therefore recommend that you have it checked at a garage soon. Good luck!

(Translated from German)

MatthiasSomm (Author)

Hey, thanks for the feedback! Your experiences sound really worrying, especially with the faulty engine control unit. My symptoms seem to be really similar, only in my case I have Viano not Vito. I'll take your advice to heart and have it checked at the garage as soon as possible. Do you remember what you paid for the repair back then? And have there been any other incidents since then? Thanks in advance and best wishes!

(Translated from German)

TweissRacer

Hey, no problem, that's what we're here for, right? Well, when the engine control unit in my Vito broke down, I had to pay around €1000 for the repair. But so far it's definitely been worth it, there have been no further incidents. Especially after they identified and fixed the problem with the ignition coil or misfiring, the engine now runs like clockwork. A real relief, I tell you. Even if it will cost you a bit at first, it's definitely worth it in the long run. So get the symptoms of your Viano checked as soon as possible so that you don't risk even greater damage. Good luck and keep us up to date! Best regards!

(Translated from German)

MatthiasSomm (Author)

Hey, your answer was super helpful, thanks! And wow, €1000 sounds really hefty, but if it stays that way and it solves the problem, then I guess it's worth the investment. I'll get my Viano in for an inspection as soon as possible so I can get the problem over with. Above all, it's reassuring to know that you haven't had any further problems since. I will definitely keep you posted! Until then, thanks again and take care! Best regards!

(Translated from German)

max1197

I think you made a mistake. A diesel has no ignition coils ;)

(Translated from German)

Karar2628

The actuation of ignition coil 1,2,3 has an electrical fault or open circuit. There is an internal component fault. Hello, i faced these problem. The car work properly , but check engine light opens

CarlyMechanic

@Karar2628

The actuation of ignition coil 1,2,3 has an electrical fault or open circuit. There is an internal component fault. Hello, i faced these problem. The car work properly , but check engine light opens

Hi Karar2628, it seems like you might be dealing with a faulty ignition coil or a wiring issue. I'd recommend starting with a visual inspection of the ignition coils and their connections. Look for any signs of damage or loose connections. If everything looks fine, you might need to use a multimeter to check for any electrical faults. Please remember to disconnect the battery before doing any electrical work to avoid any accidents. Let us know how it goes and if you have any further questions.

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